1. Field of the Invention
The present invention is in the field of internal combustion engines, and pertains more particularly to two-stroke internal combustion engines.
2. Description of Related Art
There are many sorts of two-stroke internal combustion engines known in the art at the time of the present patent application, and all of similar operating characteristics and similar problems. One commonality is that oil to lubricate cylinder and bore needs to be mixed with the gasoline used for fuel, because in such engines the crank case volume is not completely sealed from the intake and exhaust. Another is that the pistons in such engines heat very rapidly due to the two-stroke duty cycle, with each cylinder firing with every stroke. Two-stroke engines, however, typically provide substantially higher torque and substantially more power than comparable-sized four-stroke engines, but suffer from lower reliability and service life than comparable four-stroke engines. Further the two-stroke, due to the oil mixture with the fuel, are significantly polluting engines.
What is clearly needed is a two-stroke engine with an oil-bathed crankcase and an improved system for cooling the pistons.